File.



W. H. WAKFER.

FILE. APPLICATION FILED JULY14, 1911.

Patented July 29, 1913.

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airns WILLIAM HENRY WAKFER, OF SOUTH NORWOOI), ENGLAND, ASSIGNOR OFONE-HALF 'I'O SAMUEL PECK, OF CALBOURNE, WALLINGTON, ENGLAND.

FILE.

Specification of Letters Patent.

Patented July 29, 1913.

Application filed July 14, 1911. Serial No. 638,524.

T 0 all whom it may concern:

Be it known that I, IVILLIAM I-Innnr VVAKFER, subject of the King ofGreat Brltain and Ireland, residing at 67 Whitworth road, South Norwood,in the county of Surrey, England, have invented new and usefulImprovements in and Relatlng to Files, of which the following is aspecification.

This invention relates to improvements in such files in which pro-visionis made in the body of the file at intervals along its length ofclearing grooves by which the filings removed by the teeth are enabledto be discharged from the face of the file in order that the surface ofthe work shall not be scratched or defaced by the presence of suchfilings; and has for its object the construction of such a file wherebythe action of the file is insured against any deadening effect of theclogging of the teeth or grooves with collected filings, and the cuttingefiiciency of the file is considerably increased with less labor inusing the file as compared with files of known construction.

To carry the invention into effect I arrange the teeth proper of thefile parallel to one another and in one direction only and at an angleto the body of the file of from 35 to 45 in order to produce a shearingcut. At suitable intervals preferably along the whole length of thefile, in a direction transverse and at an opposite angle to the teeth ofthe file, I arrange channels or grooves which are preferably deeper thanthe teeth of the file so that such channels afford a free exit for thefilings along the stroke of the file, and at the same time effect thespecial cutting action hereinafter explained.

The channels or grooves can be of any convenient form, but arepreferably made with a more or less rounded format-ion at the bottom ofthe channels or grooves so as to maintain the maximum strength of thebody of the file to its utmost extent and at the same time afford aconsiderable amount of clearance for the filings. These channels orgrooves can be produced in any convenient manner, either initially inthe production of the file blanks by rolling, cold pressing, stamping,milling or otherwise; or the channels or grooves may be made after thefile teeth have been out (if preferred). These channels or grooves,besides affording means of clearance for the filings, at the same timeconsiderably enhance the cutting capacity of the file, without entailingany extra labor, owing to the presentation to the work of a series ofsaw-like cutting edges; each of such edges picking up a fresh grip ofthe work for its own tooth throughout the whole length of the stroke ofthe file and such grip is continued as a shearing out throughout thelength of the shearing edge of each tooth thereby considerablyprolonging the usefulness of the file, it being indis putable that ashearing tool stands considerably more wear and tear than a milling orscraping tool. These channels or grooves practically dispense with thenecessity for any double cutting, and at the same time effectuallyneutralize any tendency for lateral movement of the file, due to theangular nature of the teeth, which is counteracted by the cutting effectof the saw-like part of the teethfproduced by the channels or grooves,but if required for very dense cuts intermediate saw-like edges inalinement with the channels or grooves may be provided and these wouldpreferably be procured in the same operation as the channels or grooves.

The channels or grooves may be in any suitable spacing regulated inaccordance with the different widths or types of file so as to enhancethe cutting capacity of each type or form of file and at the same timeinsure an equipoise in effect, in whatever type or pitch of teeth may beengaged or employed. The particular angular arrangement of the teeth andgrooves toward each other enables the file to be used along or acrossthe smallest superficial surface witlr out any tendency to kick orchatter as in the case of the employment of more obtuse angles for thedisposition of the teeth and grooves.

In order that the invention may be the better understood I will nowproceed to describe the same in relation to the accompanying drawingreference being had to the letters marked thereon.

Figure l is a plan view of a portion of a file illustrating myinvention, and Fig. 2 is a cross sectional view thereof.

To carry the invent-ion into effect as shown in the drawing upon thebody a of the file teeth Z) are cut at an angle of from 35 to 45 to thebody a and transverse to said teeth 6 clearance channels or grooves care provided at an opposite angle so that the filings removed from thework by each serial set of teeth Z) are collected in the adjoiningclearance channels or grooves c and owing to the particular angularposition of each channel or groove relative to the body of the file thesaid filings cannot become embedded in or retained by the followingseries of saw-like edges of the teeth, but are freely dischargedsideward, clear of the teeth, thus leaving the teeth Z) free to take afresh hold of the Work Without any hindrance from filings previouslyremoved.

A set of secondary teeth edges (Z can be cut parallel to the grooves c.

I claim- 1. A file having a series of shearing teeth parallel to oneanother and extending in one direction only and at an angle of 35 to 45to the body of the file, and a series of clearance channels or groovesdisposed across the teeth of the file at an opposite angle so as tocollect the filings, discharge them laterally, and at the same timepresent teeth edges to take an initial grip of the Work and balance theshearing action, substantially as clescribed.

2. A file having a series of shearing teeth parallel to one another andextending in one direction only and at an angle of 38 to 45 to the bodyof the file, a series of clearance channels or grooves disposed acrossthe teeth of the file at an opposite angle so as to collect the filings,discharge them laterally, and at the same time present teeth edges totake an initial grip of the Work and balance the shearing action, andintermediate saw-like teeth edges in alinement With the teeth edgesproduced by the channels or grooves, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing Witnesses.

WVILLIAM HENRY WVAKFER. lVitnesses:

DORIS H. HIToHoooK,

CHARLES S. R. BULLOUGH.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

' Washington, D. C.

